diff --git a/model.py b/model.py
index ae11bdcbc79d038db17e0e2c5ccb2c499b8e4fde..b258be1537197417016f80e3740a2fec92396b1f 100644
--- a/model.py
+++ b/model.py
@@ -349,6 +349,7 @@ class DynamicGraphAdapter(object):
     def mode(self, value):
         self.model.mode = value
 
+    # TODO multi device in dygraph mode not implemented at present time
     def train(self, inputs, labels, device='CPU', device_ids=None):
         assert self.model._optimizer and self.model._loss_functions, \
             "model not ready, please call `model.prepare()` first"